During the bit, the seven cast members -- Kunal Nayyar (Raj), Simon Helberg (Howard), Johnny Galecki (Leonard), Mayim Bialik (Amy), Melissa Rauch (Bernadette), Jim Parsons (Sheldon) and Cuoco (Penny) -- feign surprise when they see the crew break out into dance as they prepare for a take with the trio of showrunners looking on.

Ultimately, five of the seven -- save for Galecki and Parsons' notoriously antisocial/neurotic Sheldon -- join the group performing a routine choreographed by Cuoco's sister Bri Cuoco -- to Jepsen's song, much to the showrunners' and live studio audience's pleasure.

Check out the video, which was filmed during the episode that airs Thursday night and intended as a surprise for the audience and exec producers, below.